Transitioning from BSIM4 toTransitioning from BSIM4 toTransitioning from BSIM4 to Transitioning from BSIM4 to BSIM6BSIM6

Yogesh S. Chauhan, Muhammed Karim, Sriram V., Pankaj Thakur, Yogesh S. Chauhan, Muhammed Karim, Sriram V., Pankaj Thakur, Navid Paydovosi, Angada Sachid, Ali Niknejad, Chenming Hu

University of California BerkeleyWeimin Wu Krishnanshu Dandu Keith Green Tracey Krakowski (TI)Weimin Wu, Krishnanshu Dandu, Keith Green, Tracey Krakowski (TI)

Geoffrey Coram, Sergey Cherepko (ADI)Saurabh Sirohi, Anupam Dutta, Richard Williams, Josef Watts (IBM)MariaAnna Chalkiadaki, Anurag Mangla, Wladek Grabinski, Christian

Enz (EPFL, Switzerland)

March 17, 2012

MOS-AK Workshop, Delhi

OutlineOutline

CMC CMC –– An IntroductionAn Introduction

Physics of BSIM6Physics of BSIM6

BSIM6 resultsBSIM6 results

SummarySummary

2

OutlineOutline

CMC CMC –– An IntroductionAn Introduction

Physics of BSIM6Physics of BSIM6

BSIM6 resultsBSIM6 results

SummarySummary

3

CMC MembersCMC Members

EDA Vendors, Foundries, IDMs, Fabless, Research Institutions/Consortia

AcceliconAgilent Technologies

Mentor GraphicsProPlus Design Solutions

Cypress SemiconductorElpida Memory

STARCST MicroelectronicsAgilent Technologies

AISTAnalog DevicesAnsoft

ProPlus Design SolutionsQualcommRenesas ElectronicsRicoh

Elpida MemoryFujitsu SemiconductorGLOBALFOUNDRIESIBM

ST MicroelectronicsSynopsys, Inc.Texas Instruments Inc.Toshiba Corp.

Austria MicrosystemsAWRBroadcom

RohmSamsungSilvaco

Infineon TechnologiesIntelLEAP

ToyotaTSMCUnited Microelectronics

CadenceDenso

SoitecSony

LSI CorporationMagma

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CMC History and PurposeCMC History and Purpose CMC was formed in 1996 as a collaboration CMC was formed in 1996 as a collaboration

of foundries, of foundries, fablessfabless companies, IDMs, and companies, IDMs, and EDA vendorsEDA vendorsEDA vendorsEDA vendors

Commercial or F blFoundry or IDM’s Fab

Commercial or In-House Circuit Simulator

Fabless or IDM IC Designer

Compact models provide the connectionsCompact models provide the connections Compact models provide the connectionsCompact models provide the connections.. Standard compact models enable Standard compact models enable

efficienciesefficiencies in this process.in this process.pp

5IDM – Integrated Device Manufacturer

CMC CharterCMC Charter

To promote the international nonexclusive international, nonexclusive standardization of compact pmodel formulations and the

d l i t fmodel interfaces

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CMC VisionCMC Vision Standardized compact models for all major technologies so that customer

i ti d ffi i b communication and efficiency can be enhanced.

Standard interfaces so that models can be tested faster and implemented easier. p

Better compact models for the latest ptechnologies, allowing leading edge design development cycles to shorten.

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CMC StrategyCMC Strategy

Examine, promote and standardize compact modeling efforts based upon business g pneeds.

Encourage developers to dwell on currentand near-term problems that will advance compact modeling.

Provide industry resources for monitoring and mentoring compact model developmentP id t d di ti t th Provide a standardization process to the compact model developers

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CMC standard modelsCMC standard models 19961996 BSIM3BSIM3 20002000 BSIM4BSIM4

20022002 BSIMSOIBSIMSOI

2012+ 2012+ BSIMBSIM--CMG MultiCMG Multi--Gate MOSFET ModelGate MOSFET Model BSIM6 MOSFET ModelBSIM6 MOSFET Model

20022002 BSIMSOIBSIMSOI 20042004 MEXTRAMMEXTRAM 20042004 HICUMHICUM

HiSIMHiSIM--SOI DDSOI MOSFET ModelSOI DDSOI MOSFET Model ETSOI MOSFET ModelETSOI MOSFET Model

BSIMBSIM--IMGIMG & & HiSIMHiSIM models are models are candidatescandidates

20052005 R2_CMCR2_CMC 20062006 PSPPSP 20072007 HiSIM HVHiSIM HV

candidatescandidates

20072007 HiSIM_HVHiSIM_HV 20072007 R3_CMCR3_CMC 20082008 MOSVARMOSVAR

20092009 Diode CMCDiode CMC 20092009 Diode_CMCDiode_CMC 20112011 HiSIM2HiSIM2

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CMC Models DO NOT remain staticCMC Models DO NOT remain static

Most enhancements are requested by Most enhancements are requested by members but they can also come from members but they can also come from members but they can also come from members but they can also come from the developerthe developer

CMC decides which enhancements they CMC decides which enhancements they want to pursuewant to pursuepp

CMC members test enhancements before CMC members test enhancements before they are released as a standardthey are released as a standard

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CMC Member BenefitsCMC Member Benefits Influence selection and enhancements of standardsInfluence selection and enhancements of standards

Regular interactions with modeling experts from Regular interactions with modeling experts from Regular interactions with modeling experts from Regular interactions with modeling experts from other companies and universities. other companies and universities.

Full access to CMC website: Full access to CMC website: i /CMCi /CMC C ilC il Full access to CMC website: Full access to CMC website: www.geia.org/CMCwww.geia.org/CMC------CouncilCouncil Most information produced since 2007 is only available to Most information produced since 2007 is only available to

members.members. Quarterly meeting minutes and presentationsQuarterly meeting minutes and presentations Quarterly meeting minutes and presentationsQuarterly meeting minutes and presentations Subcommittee activity reports Subcommittee activity reports Some standard model codesSome standard model codes

UniversityUniversity--supported standard model codes are supported standard model codes are yy ppppavailable to members and nonavailable to members and non--members.members.The developer grants users a perpetual, irrevocable, worldwide, The developer grants users a perpetual, irrevocable, worldwide, nonnon--exclusive royaltyexclusive royalty--free license with respect to the software free license with respect to the software nonnon exclusive, royaltyexclusive, royalty free license with respect to the software. free license with respect to the software. Users are granted the right to modify, copy and redistribute the Users are granted the right to modify, copy and redistribute the software and documentation.software and documentation.

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OutlineOutline

CMC CMC –– An IntroductionAn Introduction

Physics of BSIM6Physics of BSIM6

BSIM6 resultsBSIM6 results

SummarySummary

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BSIM6: Charge based MOSFET modelBSIM6: Charge based MOSFET model BSIM6 is the next BSIM Bulk MOSFET modelBSIM6 is the next BSIM Bulk MOSFET model Charge based core derived from Poisson’s solutionCharge based core derived from Poisson’s solution Physical Physical effects (SCE, CLM etc.) taken from BSIM4effects (SCE, CLM etc.) taken from BSIM4 Parameter names matched to Parameter names matched to BSIM4 parametersBSIM4 parameters Gummel Gummel Symmetry (symmetric Symmetry (symmetric @ @ VVDSDS=0)=0) AC SymmetryAC Symmetry

Capacitances/derivatives Capacitances/derivatives are symmetric @Vare symmetric @V =0=0 Capacitances/derivatives Capacitances/derivatives are symmetric @Vare symmetric @VDSDS=0=0 Continuous Continuous in all regions of operationsin all regions of operations Physical Physical Capacitance modelCapacitance modelyy pp

Short channel Short channel CVCV––Velocity Velocity saturation &saturation & other effectsother effects No glitches No glitches –– smooth current and capacitance smooth current and capacitance

b h ib h ibehaviorbehavior

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Physics of BSIM6 ModelPhysics of BSIM6 Model Using linearization approach and normalizationUsing linearization approach and normalization

Other models ignored

chfppiiqq

ii vqqnn

qq

222

22ln)ln(2

circled terms

No approximationNo approximation to solve the charge equationto solve the charge equation

No approximationNo approximation to solve the charge equationto solve the charge equation

We solved the charge equation using first & We solved the charge equation using first & We solved the charge equation using first & We solved the charge equation using first & second order Newtonsecond order Newton--RaphsonRaphson technique to technique to obtain obtain analytical expressionanalytical expression of of qqii

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Drain current expressionDrain current expression Drain currentDrain current

dxdQV

dxdQWIII i

TS

idiffdriftD

Second order mobility modelSecond order mobility model

dxdQV

dxdQW

dI i

TS

i

Sv

vD 2

1

Using charge linearization & normalizationUsing charge linearization & normalization

dxv

S

sat

v1

LvV

VCLWn

IiVCn

QqnCQ

sat

tvc

toxvq

Dd

Toxq

iSPq

ox

i

2,2

,2

,2

2

22

111ddss

dqqqqi

15

11

2 dsc qq

Normalized QNormalized Qii--VVGG & derivatives& derivatives

qi vs VG Error (%)

Red – Numerical Surf. Pot. model

1st derivative

Blue – BSIM6 model

2nd derivative

3rd derivative

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BSIM6 Model DevelopmentBSIM6 Model Development

Short Channel

Channel Length Modulation and

Mobility Degradation Quantum

Core

EffectsDIBLg

T t

Velocity Saturation

QEffects

Core

I-V C-VGIDL Current

Temperature Effects

FringeFringe Capacitances

Impact Ionization current

Direct tunneling gate current

Overlap capacitances

S/D Resistance/ Parasitic Noise models

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gate current capacitancesParasitic Resistance

Noise models

All effects incorporated in BSIM6.

Mobility ModelMobility Model

Mobility model has been adopted from BSIM4Mobility model has been adopted from BSIM4

UCSEUeffbsx

eff UDEVUCUA

U

11

0

bs

is

qq

1

21

where

18

MV/cm

Output conductanceOutput conductance

DIBL Effect (from BSIM4)DIBL Effect (from BSIM4)

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CV ModelCV Model Physical CV Model (including polyPhysical CV Model (including poly--depletion effect)depletion effect)

Short Channel CV Model has been added in BSIM6 0 0 Beta5in BSIM6.0.0 Beta5

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IIDSDS--VVXX Gummel SymmetryGummel SymmetryIDS vs VX

(VD=VX & VS=-VX)

X

X

dVdI

2

2XId

XI

2XdV

3

3

X

X

dVId

7Id

4

4

X

X

dVId 7

7

X

X

dVId

5

5

X

X

dVId 6

6

X

X

dVId

21

All derivatives are continuous at VDS=0

(N+1 derivatives exist, where N=DELTA)

Harmonic Balance SimulationHarmonic Balance Simulation

BSIM6 gives correct slope for all harmonicsBSIM6 gives correct slope for all harmonics

Slope=1

Slope=2Slope=3

Slope=4 Slope=5

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OutlineOutline

CMC CMC –– An IntroductionAn Introduction

Physics of BSIM6Physics of BSIM6

BSIM6 resultsBSIM6 results

SummarySummary

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Global Extraction ProcedureGlobal Extraction Procedure Single set of parameters for entire range of lengthSingle set of parameters for entire range of length Accurate evaluation of next technology nodesAccurate evaluation of next technology nodes Global extraction procedure has been developedGlobal extraction procedure has been developed Global extraction procedure has been developedGlobal extraction procedure has been developed

200+ parameters can’t be extracted using optimizer200+ parameters can’t be extracted using optimizer Step by step approach neededStep by step approach needed

Y. S. Chauhan - 24

BSIM6 Model Validation: BSIM6 Model Validation: IIDSDSVVGSGS at Vat VDSDS=0.05V for different V=0.05V for different VBSBS

Small LSmall L

Large L

BSIM6 Model Validation: Width ScalingBSIM6 Model Validation: Width Scaling

S ll LSmall L

ConclusionConclusion

Rapid developmentRapid development BSIM6.0.0 Beta7 released on 28BSIM6.0.0 Beta7 released on 28thth Feb. 2012Feb. 2012

F t h t d ti l l i 15 th !F t h t d ti l l i 15 th ! From scratch to production level in 15 months!From scratch to production level in 15 months! Charge based physical compact modelCharge based physical compact model

Physical effects & Parameter names matched to BSIM4 Physical effects & Parameter names matched to BSIM4 Physical effects & Parameter names matched to BSIM4 Physical effects & Parameter names matched to BSIM4 No new training required for engineersNo new training required for engineers

Smooth charge/current/capacitance & derivativesSmooth charge/current/capacitance & derivatives Model is Model is symmetric and continuous symmetric and continuous around Varound VDSDS=0=0

Fulfills Gummel symmetry and AC symmetryFulfills Gummel symmetry and AC symmetry Shows accurate slope for Shows accurate slope for harmonicharmonic balance simulationbalance simulation Shows accurate slope for Shows accurate slope for harmonicharmonic balance simulationbalance simulation

BSIM4’s BSIM4’s extraction methodology extraction methodology can be easily used can be easily used for BSIM6 for BSIM6 fast deployment & lower costfast deployment & lower cost

Under Under standardizationstandardization review at CMCreview at CMC

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AcknowledgementAcknowledgement

CadenceCadenceSynopsysSynopsys SynopsysSynopsys

AcceliconAccelicon ADIADI ADIADI TITI IBMIBM STST MagmaMagma All CMC MembersAll CMC Members

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BSIMBSIM--EPFL CollaborationEPFL Collaboration

BSIM and EPFL groups have agreed to BSIM and EPFL groups have agreed to collaborate on the longcollaborate on the long--termterm developmentdevelopmentcollaborate on the longcollaborate on the long term term developmentdevelopmentand and supportsupport of BSIM6 as an openof BSIM6 as an open--source source MOSFET SPICE models for worldwide use.MOSFET SPICE models for worldwide use.MOSFET SPICE models for worldwide use. MOSFET SPICE models for worldwide use. This is an exciting opportunity to leverage This is an exciting opportunity to leverage the long history and large user base of thethe long history and large user base of thethe long history and large user base of the the long history and large user base of the BSIM model with the long experience and BSIM model with the long experience and active role of EPFL for furthering chargeactive role of EPFL for furthering charge--active role of EPFL for furthering chargeactive role of EPFL for furthering chargebased compact model.based compact model.

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